Applicability of GSO scintillators for well logging

Cerium-doped gadolinium oxyorthosilicate (GSO:Ce) was developed as a scintillating material for application in positron emission tomography. The fundamental properties of this material were studied, with particular attention given to properties relevant to nuclear well logging applications and their temperature dependence. Initial evaluations indicated that this material had a number of properties which seemed to make it a favorable candidate for well logging applications, such as the reported decay-time constant of 60 ns. Subsequent studies showed the presence of a longer, 600-ns. decay constant, which, coupled with its extremely high thermal neutron absorption cross section and relatively low light output, raised questions about its suitability. The temperature dependence of GSO:Ce was investigated to better evaluate its applicability as a gamma-ray detector for nuclear well logging applications. It is noted that the main advantage of GSO, compared to other scintillators that can be used for well logging applications. is the increase in detection efficiency that can be achieved without the need for cooling the detector